NAME

c4 - Chip’s Challenge combined converter

SYNOPSIS

c4 [-INTYPE] INFILENAME [-OUTTYPE] OUTFILENAME
c4 allows one to translate between the several different types of files
used to represent level sets for the game Chip’s Challenge.
c4 expects there to be two files named on the command-line. c4 reads
the levels stored in the first file, and then writes the levels out to
the second file. The format to use with each file usually can be
inferred by c4 by examining the filenames. If not, then it may be
necessary to use switches before one or both filenames to indicate
their type.
There are four different types of files that c4 understands.
-D MS data file (*.dat).
This is the file type used by Chip’s Challenge for Microsoft Windows
3.x. It is the file type used by most other programs, such as ChipEdit
and Tile World.
-R Lynx ROM file (*.lnx, *.lyx)
This "file type" is actually just a ROM image of the original Chip’s
Challenge for the Atari Lynx handheld. It is used by Lynx emulators
such as Handy.
-P MS-DOS fileset (directory of *.pak files)
This is the format used by the MS-DOS port of Chip’s Challenge. In this
case, the filename given on the command line actually names a
directory, containing *.pak files.
-T textual source file (*.txt)
This file type is native to c4. It is a plain text file, which allows
levels to be defined pictorially using a simple text editor. A complete
description of the syntax of these files is provided below.

EXAMPLES

c4 mylevels.txt mylevels.dat
Create a .dat file from a textual source file.
c4 -P levels -D doslevels.dat
"levels" is a directory of MS-DOS *.pak files. c4 translates the
directory contents into a single .dat file. Note that the switches in
this example are optional, as c4 would be able to infer the desired
formats.
c4 mylevels.dat chipsch.lnx
Embed the levels from the .dat file into a Lynx ROM file. Note that c4
does NOT create chipsch.lnx. You must provide the ROM image file, which
c4 then alters to contain your levels. (Obviously, you should not use
this command on your master copy of the ROM file.)
c4 chipsch.lnx -T out
Output the levels in the .dat file as a text file. Here the -T switch
is needed to indicate that a text file is the desired output format.
When producing a text file, c4 will attempt to produce legible source,
but the results will often not be as good as what a human being would
produce. (In particular, c4 cannot draw overlays.)

NOTES

Be aware that there can be various problems when translating a set of
levels using the MS ruleset to one of the Lynx-only file formats.
There are numerous objects and configurations in the MS ruleset which
cannot be represented in the Lynx ruleset. Usually c4 will display a
warning when some aspect of the data could not be transferred intact
because of this.
The remainder of this documentation describes the syntax of the textual
source file format.

LAYOUTOFTHEINPUTFILE

The source file is broken up into subsections. Each subsection defines
a separate level in the set.
The subsections are separated from each other by a line containing
three percent signs:
%%%
A line of three percent signs also comes before the first level and
after the last level, at the end of the source file.
Any other line that begins with a percent sign is treated as a comment,
and its contents are ignored.
Beyond these things, the source file consists of statements.
Statements generally appear as a single line of text. Some statements,
however, require multiple lines. These multi-line statements are
terminated with the word end appearing alone on a line.

INPUTFILEHEADERSTATEMENTS

There are a couple of statements that can appear at the very top of the
source file, before the first level subsection.
ruleset [ lynx | ms ]
The ruleset statement is the most important of these. It defines the
ruleset for the level set. If the ruleset statment is absent, it
defaults to lynx.
maxlevel NNN
The maxlevel statement specifies the number of the last level in the
.dat file. By default, this value is provided automatically and does
not need to be specified.
In addition to the above, a set of tile definitions can appear in the
header area. See below for a full description of the tiles multi-line
statement. Any tile definitions provided here remain in force
throughout the file.

INPUTFILELEVELSTATEMENTS

Within each level’s subsection, the following two statments will
usually appear at the top.
title STRING
password PASS
The title statement supplies the level’s title, or name. The title
string can be surrounded by double quotes, or unadorned. The password
statement supplies the level’s password. This password must consist of
exactly four uppercase alphabetic characters.
If the level’s number is 150 or less, the password statement may be
omitted. In that case the level’s password will default to match that
level in the original Lynx set. (N.B.: The Lynx ROM file format does
not provide a mechanism for setting passwords, so in that case the
default password will be used regardless.)
The following statements may also appear in a level subsection.
chips NNN
The chips statement defines how many chips are required on this level
to open the chip socket. The default value is zero.
time NNN
The time statement defines how many seconds are on the level’s clock.
The default value is zero (i.e., no time limit).
hint STRING
The hint statement defines the level’s hint text. As with the title
statement, the string can either be unadorned or delimited with double
quotes. If a section contains multiple hint statements, the texts are
appended together, e.g.:
hint This is a relatively long hint, and so it
hint is helpful to be able to break it up across
hint several lines.
Note that the same can be done with title statements.
tiles
DEF1
DEF2
...
end
The tiles multi-line statement introduces one or more tile definitions.
The definitions appear one per line, until a line containing end is
found. Note that the tile definitions given here only apply to the
current level. A complete description of tile definitions is given
below.
map [ X Y ] map [ X Y ]
LINE1 LINE1
LINE2 LINE2
... ...
and end
OVER1
OVER2
...
end
The map statement defines the actual contents of (part of) the level’s
map. The line containing the map statement can optionally include a
pair of coordinates; these coordinates indicate where the the section
will be located on the level’s map. If coordinates are omitted, the
defined section will be located at (0 0) -- i.e., the upper-left corner
of the level. The lines inside the map statement pictorially define the
contents of the map section, until a line containing and or end is
encountered. When the map is terminated by and, then the lines defining
the map section are immediately followed by lines defining an overlay.
The overlay uses the same origin as the map section (though it is
permissible for the overlay to be smaller than the map section it is
paired with). A complete description of the map and overlay sections is
given below.
border TL
The border statement specifies a tile. The edges of the map are then
changed to contain this tile. Typically this is used to enclose the
level in walls.
The following statements are also available, though they are usually
not needed. They provide means for explicitly defining level data, for
the occasional situation where the usual methods are more cumbersome.
creatures X1 Y1 ; X2 Y2 ...
The creatures statements permits explicit naming of the coordinates in
the creature list. Pairs of coordinates are separated from each other
by semicolons; any number of coordinate pairs can be specified. There
can be multiple creatures statements in a level’s subsection.
traps P1 Q1 -> R1 S1 ; P2 Q2 -> R2 S2 ...
The traps statement permits explicit naming of the coordinates for
elements in the bear trap list. Coordinates are given in one or more
groups of four, separated by semicolons. Each group consists of the x-
and y-coordinates of the brown button, an arrow (->), and then the x-
and y-coordinates of the bear trap. Any number of traps statements can
appear in a level’s subsection.
cloners P1 Q1 -> R1 S1 ; P2 Q2 -> R2 S2 ...
The cloners statement permits explicit naming of elements in the clone
machine list. It uses the same syntax as the traps statment, with the
red button’s coordinates preceding the coordinates of the clone
machine.
level NNN
The level statement defines the level’s number. By default it is one
more than the number of the prior level.
field NN B01 B02 ...
The field statement allows fields to be directly specified and embedded
in the .dat file. The first argument specifies the field number; the
remaining arguments provide the byte values for the actual field data.
These statements are only meaningful in conjunction with producing a
.dat file.

DEFININGTILES

A tile definition consists of two parts. The first part is either one
or two characters. The characters can be letters, numbers, punctuation
-- anything except spaces. The second part is the name of a tile or a
pair of tiles. The characters then become that tile’s representation.
Here is an example of some tile definitions:
tiles
# wall
* teleport
rb red button
@ chip south
end
(Note that a single tab character comes after the characters and before
the tile names.) Once these definitions have been provided, the newly-
defined characters can then be used in a map.
The above definitions all use singular tiles. To define a pair of
tiles, combine the two names with a plus sign, like so:
tiles
X block + bomb
G glider north + clone machine
end
Notice that the top tile is named first, then the bottom tile.
The tiles statement is the only statement that can appear in the
header, as well as in a level’s subsection. Tile definitions in the
header are global, and can be used in every subsection. Tile
definitions inside a subsection are local, and apply only to that
level.
A number of tile definitions are pre-set ahead of time, supplying
standard representations for some of the most common tiles. (If these
representations are not desired, the characters can always be
redefined.) Here are some of the built-in definitions:
# wall $ computer chip
, water H socket
= ice E exit
& fire [] block
6 bomb ? hint button
See below for the complete list of tile names and built-in definitions.
A few groups tiles allow one to specify multiple definitions in a
single line. For example:
tiles
G glider
end
This one definition is equivalent to the following:
tiles
Gn glider north
Gs glider south
Ge glider east
Gw glider west
end
(Note that "G" by itself is still undefined.) All creatures, including
Chip, can be defined using this abbreviated form.
Doors and keys are the other groups that have this feature; the
following definition:
tiles
D door
end
is equivalent to:
tiles
Dr red door
Db blue door
Dy yellow door
Dg green door
end

MAPSECTIONS

Once all the needed tiles have defined representations, using the map
statement is a simple matter. Here is an example:
map
# # # # # #
# & & # # #
[] H E #
# & $ # # #
# # # # # #
end
This is a map of a small room. A block stands in the way of the
entrance. Three of the four corners contain fire; the fourth contains a
chip. On the east wall is an exit guarded by a chip socket.
Note that each cell in the map is two characters wide. (Thus, for
example, the octothorpes describe a solid wall around the room.)
Here is a larger example, which presents the map from LESSON 2:
tiles
B bug north
C chip south
end
map 7 7
# # # # # # #
# $ #
# #
# # # # # # # # # # # #
# # # # B , , $ #
# E H # # B , , [][]C ? #
# # # # B , , $ #
# # # # # # # # # # # #
# #
# $ #
# # # # # # #
end
There are a couple of different ways to fill a cell with two tiles.
The first way is to simply use tile definitions which contains two
tiles:
tiles
X block + bomb
G glider east + clone machine
end
map 12 14
# #
6 E #
# # X
G
end
The second way is to squeeze two representations into a single cell.
Obviously, this can only be done with both representations are a single
character.
tiles
[ block
G glider east
+ clone machine
end
map 12 14
# #
6 E #
# # [6
G+
end
In both cases, the top tile always comes before the bottom tile. Note
that you can "bury" a tile by placing it to the right of a space:
map
# # # # # #
6 6 6E #
# # # # # #
end
Any number of map statements can appear in a level’s subsection. The
map statements will be combined together to make the complete map.

OVERLAYSECTIONS

Every map statement can optionally include an overlay section. This
overlay permits button connections and monster ordering to be defined.
The overlay is applied to the same position as the map section it
accompanies. The overlay can duplicate parts of the map section it
covers, and any such duplication will be ignored. The only characters
in the overlay that are significant are the ones that differ from the
map section it covers. These characters are treated as labels. Labels
are always a single character; two non-space characters in a cell
always indicates two separate labels. Any non-space characters can be
used as labels, as long as they don’t match up with the map.
An overlay section defines a button connection by using the same label
in two (or more) cells. One of the labelled cells will contain either a
bear trap or a clone machine, and the other will contain the
appropriate button. If there are more than two cells with the same
label, all but one should contain a button.
Characters that only appear once in an overlay, on the other hand,
indicate creatures. The characters then indicate the ordering of the
creatures in the creature list with respect to each other. The ordering
of characters is the usual ASCII sequence (e.g., numbers first, then
capital letters, then lowercase letters).
For example, here is a map with an overlay that demonstrates all three
of these uses:
tiles
G glider east
+ clone machine
r red button
* beartrap
b brown button
end
map
G v #
G+ * r * G+ b & # r
G+ * r # # r
# > b b G < # #
and
2 v #
A c C d C d & # A
B a C # # B
# > a c 1 < # #
end
In this example, capitals are used for the clone machine connections,
lowercase for the bear trap connections, and numbers are used for the
creature ordering.
(Note that the gliders atop clone machines are not numbered. While it
is not an error to include clone machine creatures in the ordering,
they are ignored under the MS ruleset.)
It is not necessary to reproduce any of the map section’s text in the
overlay section. Blanks can be used instead. The ignoring of matching
text is simply a feature designed to assist the user in keeping the
overlay’s contents properly aligned.
The traps, cloners, and creatures statements can be used in lieu of, or
in conjunction with, data from overlay sections. In the case of the
creature list, items are added to the list in the order that they are
encountered in the source text.
If a level contains no overlay information and none of the above three
statements, then this information will be filled in automatically. The
data will be determined by following the original Lynx-based rules --
viz., buttons are connected to the next beartrap/clone machine in
reading order, wrapping around to the top if necessary. (Likewise, the
creature ordering is just the order of the creatures in their initial
placement, modified by swapping the first creature with Chip.) Thus, if
you actually want to force an empty bear trap list, clone machine list,
or creature list, you must include an empty traps, cloners, and/or
creatures statement.

LICENSE

c4, Copyright (C) 2003-2006 Brian Raiter <breadbox@muppetlabs.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and documentation (the "Software"), to deal in
the Software without restriction, including without limitation the
rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.